Screen



Patented Oct. 12, 1954 UNITED STATES PATENT OFFICE SCREEN Edward Townsend, Hu

to The Sandy dson Falls, N. Y., assignor Hill Iron & Brass Works, Hudson 1 Claim. 1

Thi invention relates to improvements in flat screens used in the paper making industry for screening paper making stock.

The principal objects of the invention are directed to the provision of mechanism for releasably securing a plurality of fiat perforated screen plates in adjacency in a screen vat.

The mechanism is constructed and arranged to facilitate the ready and easy securing of the screen plates in position as well as releasing of the plates as may be desired and necessary.

All of the above objects I accomplish by means of such structure and relative arrangements of parts thereof, as will fully appear by a perusal of the description below and by various specific features which will be hereinafter set forth.

To the above cited and other ends and with the foregoing and various other novel features and advantages and other objects of my invention as will become more readily apparent as the description proceeds, my invention consists in certain novel features of construction and in the combination and arrangement of parts as will be hereinafter more particularly pointed out in the claims hereunto annexed and more fully described and referred to in connection with the accompanying drawings wherein:

Fig. 1 is a small scale plan view of a flat screen apparatus embodying the novel features of the invention;

Fig. 2 is a transverse sectional'view on the line 2-2 of Fig. 1;

Fig. 3 is a plan view on the line 3-3 of Fig. 2; and

Fig. 4 is a sectional elevational view on the line 4-4 of Fig. 1.

Referring now to the drawings more in detail, the invention will be fully described.

Screen apparatus, commonly called a flat screen, is represented by 2 in Fig. 1. In a general way, the apparatus includes a vat having longitudinal side walls 4 and transverse end walls 6. Flat metallic screen plates 8 which are provided with very small apertures indicated by 8' extend between the walls 4, and are supported by transverse members l0.

Adjacent edges of adjacent plates are held in place on the member Ill by hold-downs I2, all as will hereinafter appear.

Vats for flat screens are formed from wood or from metal plate as may be desired. The present invention will be described with reference to a vat formed from metal plate for purposes of disclosure. The vat and plates form no part of the present invention and need not be described more in detail.

The transverse members In referred to are best shown in section in Fig. 4 and are U-shaped in transverse cross section and have opposite side walls l4 and bottom walls l6. Opposite ends of the members It are secured to the vat side walls 4 in suitable manner as by welding indicated by l8. Elongated screen plate supports 24 are welded to inner sides of the side walls [4 as indicated at 22.

Adjacent edges of adjacent screen plates 8 rest on the transverse members and the hold-downs l2 have side edges complemental to those of adjacent screen plates. The hold-downs are urged downwardly by means now to be described and thereby clamp the sides of the screen plates 8 to the transverse members Ill. It will be understood that the mechanism to be described is common to each transverse member I 0.

A carriage indicated by 26 includes a pair of elongated side rails 28, a plurality of longitudinally spaced saddles 30 and a plurality of longitudinally spaced plates 32 which form an integral carriage structure. The carriage may be separate secured together components or the carriage structure may be formed from sheet metal or by casting, all as may be desired.

The hold-down I2 is provided with longitudinally spaced studs 34 depending therefrom which have heads 36. The spacing of the saddles 30 correspond to the spacing of the studs 34 and the saddles have slots to receive the studs 34, as shown in Fig. 3. Transverse pins 38 are secured to the undersides of the side rails 28 as by welding or the like. Lower ends of plates 32 and upper sides of pins 38 provide slots therebetween.

Threaded posts 4|] have lower ends secured to wall [6 and extend upwardly therefrom. Tracks 42 have holes in opposite ends thereof and receive the posts 40. Tracks 42 are carried by adjacent posts 40 which constitute a pair thereof.

The carriage 26 is movable back and forth within the transverse member It). It moves to the right for locking the screen plates in place and to the left for releasing said plates. The tracks decline from left to right and are disposed in the slots formed between the lower ends of plates 32 and the transverse pins 38 so that as the carriage is moved to the right in locking direction, it is moved downwardly whereby with the heads 36 of studs 34 below the saddles 30 the hold-down is urged downwardly for clamping adjacent edges of adjacent plates 8.

As the carriage is moved in releasing direction to the left, the carriage moves upwardly to release the heads of the studs and said studs pass out of the slots of the saddles 30.

Nuts 4| are adjustable on the posts 40 to limit the upward movement of the tracks 42 thereon and the parts are so arranged that the desired up and down movement of the carriage is accomplished during its movement in opposite directions.

A header 44 is secured between the ends of the members 28 of the carriage l2. A screw 46 extends through a side wall 4. of the vat and through washers 48 and a sleeve 50. A collar 52 is provided on the screw 46 at the inner side of the header 44 and a nut 54 is in threaded engagement with the said screw. A handle 56 is fixed to the outer end of the screw.

The carriage is moved back and forth by the handle 56 and screw so that the studs 40 of the hold-down are engaged and released by the saddles 30. With the carriage to the right in locking position, the nut 54 may be turned to urge the carriage in locking direction so that the saddles urge the hold-down l2 downwardly. In this way, the hold-down clamps adjacent edges of adjacent screen plates to the member Hi.

The tracks may be adjusted to facilitate the desired downward pressure of the saddles on the studs of the hold-down, and a guide or guides 58 is provided on the lower wall It of the member ID for the member 44 of the carriage to slide upon in its movement in opposite directions.

The invention may be embodied in other specific forms without departing from the essential characteristics thereof. Hence, the present embodiments are therefore to be considered in all respects merely as being illustrative and not as being restrictive, the scope of the invention being indicated by the appended claim rather than by the foregoing description, and all modifications and variations as fall within the meaning and purview and range of equivalency of the appended claim are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the United States is:

Apparatus for supporting and securing adjacent longitudinal screen plates extending transversely between opposite walls of a screen vat comprising in combination, an elongated member having opposite ends secured to said walls provided with a lower horizontal longitudinal wall and upper transversely spaced portions for supporting spaced longitudinal portions of adjacent screen plates, longitudinally spaced posts having lower ends secured to said wall and extending vertically upwardly therefrom and arranged whereby adjacent posts constitute a pair thereof, elongated tracks extending between and carried by posts of a pair thereof and declining from one to the other of said posts, an elongated holddown for overlying side portions of adjacent screen plates having studs spaced therealong and depending therefrom provided with heads on lower ends thereof, an elongated carriage structure movable in opposite directions and including transversely spaced elongated side members disposed at outer longitudinal sides of said tracks and saddles secured to upper edges thereof and plates secured thereto which depend relative to said saddles, said saddles provided with open ended slots for receiving said studs above the heads thereof adapted to bear on said heads, and pins secured to lower edges of the carriage side members extending transversely of said carriage, said pins and lower edges of said plates of the carriage disposed below and above and arranged to engage said tracks whereby as the carriage is moved in clamping direction and in the direction of the declination of the tracks the studs are received in the slots of the saddles and the carriage is urged downwardly by said tracks so that the saddles act on the heads of said studs to urge the hold-down downwardly while when said carriage is moved in an opposite direction the plates and pins in cooperation with the tracks move the carriage upwardly while the saddles are moved from off the heads of the studs.

References Cited in the file of this patent UNITED STATES PATENTS Number 

